Present damage-risk criteria (DRC) for daily 8-hr exposure to intermittent noise are based on extrapolation from meager data. It is certain that the equal-energy hypothesis traditionally used (a hypothesis that assumes that the temporal pattern is irrelevant: only the total energy matters) leads to DRC that are too conservative, since no account is taken of the recuperative powers of the ear between noise bursts. On the other hand, a recent American DRC sponsored by the Committee on Hearing, Bioacoustics (CHABA) of the National Research Council may not be conservative enough, according to empirical evidence that has since accumulated. Therefore it is proposed to determine DRC for intermittent noise directly, based on the assumption that any pattern of noise exposure over an 8-hr period is safe if the auditory fatigue (temporary threshold shift, or TTS) thereby produced has disappeared after 16 hr of rest. Normal-hearing young adults will be exposed for 6 or 8 hr to noise patterns with duty cycles ranging up to 40 min, with on-fractions of 1/2, 1/4 and 1/8. The intensity level for each such pattern will be gradually increased in successive sessions until the particular TTS is produced that just barely recovers in 16 hr. DRC based on the results will then be constructed.